Rurouni Ben
by SaurusRock625
Summary: Full summary inside! Ben goes to Japan, and meets up with Himura 'Battosai' Kenshin. 'Nough said, true believers!
1. Chapter 1

_**Summary: Having had enough of how he was being treated in Bellwood, Ben Tennyson leaves for the country of feudal Japan. He meets up with a swordsman that has a cross-shaped scar on his left cheek, and decides to stay at a sword arts dojo that practices "Katsujin Ken", or "Swords that give life". Now watch as Ben Tennyson takes this new and strange world by storm! Takes place in Omniverse.**_

_**(Aliens that won't be included because I don't like them include Walkatrout, The Worst, Spitter, Molestache, Kickin' Hawk, and Toepick.)**_

_**Disclaimer: I don't own Ben 10, or Rurouni Kenshin/Samurai X!**_

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"Normal Speech"

_'Thoughts'_

_Omnitrix Database_

**"Yelling"**

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_**Leaving for Japan!**_

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On a cargo ship heading for the distant country of Japan, there was a single passenger who wasn't a part of the crew. He had shaggy brown hair, neon green eyes, and pale skin. He was wearing a black and green shirt with the number '10' on the chest, a pair of brown cargo pants, and a pair of white and green sneakers. He also had a white wristwatch on his wrist that had a square black faceplate with a green hourglass mark in the center. He appears to be about sixteen years old, and has a look in his eyes that suggested that he was betrayed by everyone he ever cared about.

This is Benjamin Kirby Tennyson, wielder of the Omnitrix and hero of the universe. And about the whole betrayal thing? Well, you aren't too far from the truth. Earlier that day, Ben had failed in a mission to stop Vilgax from destroying a nuclear power plant. This wouldn't have been so bad if it didn't leave an entire town dead from radiation poisoning. This caused Ben to slip into a deep depression, which only worsened as his family and friends stopped paying attention to him all together.

Eventually, Ben left Bellwood without so much as a word of warning. He managed to get a ticket on a cargo ship to go to Japan. He figured that the rural area and change of culture might be what he needed to calm down and reflect on what went wrong in his life.

"Well isn't this an oddly familiar situation." Said a voice from a nearby crate.

Ben turned to look at the speaker, and saw that it was Azmuth. Azmuth was a Galvan that created the Omnitrix, and looked like a gray skinned anthropomorphic frog with bulbous green eyes, long appendages hanging from his upper lip which gave the appearance of a mustache, and was wearing a black and green toga with armor underneath it. His eyes held sympathy for what the teen was going through.

"Oh... Hey, Azmuth." Ben greeted halfheartedly.

"I heard about the incident from Maxwell. And I can most certainly say that I understand what you're going through." Azmuth said as he walked over to Ben.

Azmuth thought back to the beginning of the Hybreed's invasion. He thought about how he couldn't do anything to stop the temporary destruction of his entire race. The very thought was enough to send chills down his spine.

"The loss of all those innocent lives was hard on you, wasn't it?" Azmuth asked.

"I can still hear them. Their screams of pain and terror haunting every corner of my mind! I let them all down! I should've been there sooner!" Ben said with his face buried in his hands.

Azmuth was no stranger to this behavior. It was exactly how he was when he failed to save his own species from certain doom. But he also knew that sitting around moping wasn't going to solve anything! Besides, there was something that Azmuth needed to do that involved the Omnitrix.

"While it's true that you COULD have gotten there in time, I'm afraid the fact remains that you cannot change the past. Besides, I need to make an upgrade to the Omnitrix in order to help you fight stronger enemies." Azmuth explained.

Ben was puzzled by the Galvan's words, but paid attention anyway. Azmuth walked over to the Omnitrix, removed the core stating that it would only be temporary, and pulled out a green Polymorphic Crystal. He put the crystal into the Omnitrix, reattached the core and faceplate, and like that the Omnitrix began to transform.

It still stayed on his wrist, but the faceplate became circular and the band split to form what appeared to be four green 'Ultimate' spikes that met in the middle under his wrist. There were also two activation buttons on both sides of the dial, and the hourglass was now totally green.

"What happened to the Omnitrix?" Ben asked.

"I have upgraded it. It now has the evolution function of Albedo's Ultimatrix, but it is far more powerful! It can take your aliens beyond even the Ultimate forms!" Azmuth explained.

Ben was amazed by this new development! Now he had even more power than before at his disposal, and he had his Ultimate forms back! But that's when the Galvan scientist decided to break out some more news.

"However, I'm afraid that with certain aliens that are in your arsenal you can only change straight into their Ultimate forms. You won't be able to turn into their devolved states anymore." Azmuth said.

While Ben was happy about having new powers, he didn't like the trade-off very much. But he knew that there was nothing that he could do about this particular situation. Ben's eyes lit up with a renewed fire of determination, and vowed that he wouldn't allow any more innocent people to die because he couldn't do anything! The ship would be docking soon, so Ben picked up his supplies and went to the upper deck while Azmuth teleported back home.

Once Ben had disembarked from the ship, he started on his way along the winding paths of this country. He knew that the first thing he had to do was find a way to convert his American currency into Japanese fare. And right now, he doesn't have much money as it is. Ben was broken from his thoughts when he ended up bumping into someone.

"Oh, sorry. I didn't see you there!" Ben apologized.

It was a man who was apparently a samurai judging from his choice of clothing and the sword strapped to his left hip. He had lavender colored eyes with reddish orange hair, was a bit on the skinny side, and had a cross shaped scar on the left side of his face.

"Please, there is no need to apologize. This one was not watching where he was going. It is this one who should be apologizing to you!" said the strange man.

Ben was a little weirded out by the man's odd way of talking. It was like he was degrading himself by speaking in the third person, but Ben could somehow tell that this was a man he could trust.

"My name's Ben. Ben Tennyson. Who are you?" Ben asked.

"Kenshin. This one's name is Himura Kenshin." said the now-named Kenshin.

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_**This is my new story, guys! I hope you all enjoy this, because I have put a great deal of effort into the creation of this chapter! Now, I'd like your honest opinions here. Should I have Ben learn the Hiten Mitsurugi style of kenjutsu, or not? And who should he be paired with in this story? Kaoru? Megumi? Or Misao? Please let me know in the reviews, or through PM. I promise to take all ideas into account!**_


	2. Chapter 2

_**Here we are with the newest chapter of Rurouni Ben! A lot of people seem to like the idea of me pairing Ben up with Misao, and I like that idea. However, there is one thing that I'm still not so certain about. Should I give Misao an Omnitrix of her own? And if so, what would it even look like?! If you have ideas for that, feel free to let me know.**_

_**Disclaimer: I still don't own Ben 10, or Rurouni Kenshin/Samurai X!**_

"Normal Speech"

_'Thoughts'_

_Alien Database_

**"Yelling"**

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_**Sparring Session!**_

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It's been half a year since Ben arrived in Japan and met Kenshin, and Ben could honestly say that he was perfectly content with this more rural lifestyle. I mean, sure Japan may not have his favorite blended drink, but at least he had some peace of mind. He had no alien villains to fight, no Plumbers protocol to follow, and more importantly he was finally free! Free of his old way of life that came with it, and finally free to just do things his way!

Wandering the countryside with Kenshin was definitely a good thing in Ben's opinion. He was able to just chill, take in the scenery, and just enjoy life! Something he couldn't do when he was a member of the Plumbers. They may not have much money, but there was always plenty of food in the wilderness. Usually in the form of fish and edible plants. Kenshin was also a great Kenjutsu teacher, and decided to at least teach Ben the basics of sword arts.

Right now, they were in the middle of a clearing standing at opposite sides. Kenshin and Ben were about to spar with one of his aliens to make sure Ben's skill with his alien forms doesn't rust. Kenshin had his sakabatō drawn, and Ben had activated his Omnitrix. At least that's what he's still calling it right now. Since he didn't know what the new function of the Omnitrix was capable of, Ben didn't know if he should change the name of the device or not.

"Okay, Ben. Are you ready to spar as one of your aliens?" asked Kenshin.

"Bring it on!" said Ben.

In a flash of green light, Ben started to transform into one of his more well-known aliens. He grew twenty feet tall and became very muscular. His overall body type was that of a humanoid Ankylosaurus with camo green skin. His head now possesses a dark blue, Ankylosaurus-like helmet with three spikes running down the top, which are silver. On the sides of the helmet, he has black ram horns that point down.

He also has a dark blue turtle shell with long silver spikes running down each side. His plated chest and torso are also dark blue with five spikes on each end. His tail has a blue mace on the end that had silver spikes on it, and his knuckles have silver barrels on them. He also had an Omnitrix mark four 'Ultimate' spikes jutting out of it located in the center of his chest.

**"ULTIMATE HUMUNGOUSAUR!"**

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_Omnitrix Database Entry_

_Species: Evolved Vaxasaurian_

_Given Name: Ultimate Humungousaur_

_Powers Include: Enhanced Strength, Enhanced Durability, Powerful Roar, Spiked Shell, Mace Tail, Missile Generation, and Missile Hands._

_Weaknesses: Lacks the ability of the devolved Vaxasaurian that allows it to change size. His missiles can be absorbed. Vulnerable to electricity._

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Kenshin was amazed by the evolved Vaxasaurian. Never in his lifetime did the former Hitokiri hope to see such a sight. But he had no time to revel in his amazement, as Ultimate Humungousaur's hands changed into what appeared to be cannon barrels. Four on each hand. He pointed them at Kenshin, but nothing happened.

"Oro?" said a confused Kenshin.

Suddenly, a barrage of silver colored missiles was released from the barrels on Ultimate Humungosaur's hands! And they were heading straight for Kenshin! Due to his years of experience in the Bakumatsu war, Kenshin was able to dodge all of the missiles and get in close. Ultimate Humungousaur raised his arm to slam it down on his opponent, but Kenshin was faster and landed a clean hit in the side of Ultimate Humungousaur's armor!

It may not have caused too much damage, but it still hurt like heck! Kenshin took up a Battojutsu stance while Ultimate Humungousaur had his guard down. The look in his eyes was one that said he was serious about winning this spar.

"A single hit won't be enough to defeat you in this form, I see. Then this should be enough to defeat you." said Kenshin.

Kenshin swung his sword about nine times in a row, and every swing hit its mark. With the damage done, Ultimate Humungousaur fell to the ground and changed back into Ben.

"Hiten Mitsurugi Ryū... Ryūsōsen." said Kenshin as he stated the name of the move.

Ben got himself back to his feet as the pain started to die down to a dull throb. Thanks to the defensive power of Ultimate Humungousaur, Ben didn't take any damage that would impair him in any way.

"It looks like I can't beat you the way I am now." said Ben with a friendly grin.

"No... But that was a very good try." said Kenshin. "Can you walk?"

Ben nodded, and started to walk towards their next destination. They were heading for the place where they would unknowingly embark on a grand adventure. And the name of that place was... Tokyo!

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_**Sorry that it's short, but I hope you all enjoy it! Now please remember that if you want Misao to have an Omnitrix tell me what you think it should look like, and send in some aliens that you want her to have. Good luck, and enjoy the story!**_


End file.
